Transgenic mice

The Precision Mouse Engineering Core generates transgenic mice by pronuclear microinjection of foreign DNA fragments into one-cell-stage mouse embryos. On average, it takes about 3 months to 4 months to generate a transgenic mouse strain.

The Precision Mouse Engineering Core can help investigators design transgenic DNA constructs. Once a transgenic construct has been assembled, the investigator files a request for microinjection services.

Core personnel then excise the transgene from the plasmid backbone and prepare it for microinjection. They also set up superovulation and matings to obtain one-cell-stage embryos for microinjection and prepare pseudopregnant surrogate mothers for embryo transfer procedures.

The core typically injects the DNA construct into fertilized eggs over a period of two days. Then the core transfers microinjected embryos into surrogate mothers who develop these embryos to term.

Once pups are born from these eggs, the core collects tail biopsies to prepare genomic DNA. The core screens this DNA by polymerase chain reaction analysis for the presence of transgenic DNA. The core breeds transgenic animals to establish a cohort of mice that investigators can use to study the phenotypic consequences of transgene expression.